1. Field of the Invention
The invention relates to an ink jet printhead comprising: a body having first and second opposite main faces, a plurality of pressure chambers and a corresponding plurality of nozzles being provided in the body, each pressure chamber extending between the first main face of the body and one of the nozzles and each nozzle extending between one of the pressure chambers and the second main face of the body; a membrane having first and second main faces, said membrane being connected to the body with its second main face facing the first main face of the body;
an actuator plate having first and second main faces, the second main face of said actuator plate facing the first main face of the membrane, said actuator plate comprising a plurality of actuator elements corresponding to the plurality of pressure chambers, the positions of the actuator elements in the actuator plate corresponding to the positions of the pressure chambers in the body, each actuator element being conceived to change its dimension in the direction of the thickness of the actuator plate upon application of a suitable voltage to the actuator element. The invention also relates to an ink jet printer comprising an ink jet printhead of this type.
2. Description of the Related Art
An ink jet printhead of the type set forth is known from U.S. Pat. No. 4,599 628. In the known printhead, the actuator plate is a piezoceramic plate. The actuator elements are embossed parts of the actuator plate that overly the pressure chambers. The actuator elements are provided with film electrodes to which electrical connections have to be made outside the area above the pressure chambers so that the mass of the electrical connections does not affect the resonance frequency of the actuator elements. Consequently, the area of the actuator elements necessarily exceeds the area of the pressure chambers so that the total area of the actuator plate is comparatively large. Moreover, many electrical connections have to be made with great precision which is time-consuming and increases the manufacturing cost of the device.